MR. CLUTCH: Tyler Moore hits a two-run single in the top of the eighth inning to lead the Nationals to a 3-2 come-from-behind victory over the Cardinals yesterday in Game 1 of the ALDS in St. Louis. Photo: AP

MR. CLUTCH: Tyler Moore hits a two-run single in the top of the eighth inning to lead the Nationals to a 3-2 come-from-behind victory over the Cardinals yesterday in Game 1 of the NLDS in St. Louis. (
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ST. LOUIS — The chess match between managers began in the middle innings and ended with the Nationals’ Davey Johnson calling “checkmate” on a postseason stage for the first time in 15 years.

Tyler Moore’s pinch-hit, two-run single in the eighth inning was the most significant move that worked for the former Mets manager yesterday, helping the Nationals steal a victory from the Cardinals, 3-2 in Game 1 of the NLDS at Busch Stadium.

In a sloppy game, each team left 10 runners on base, but the Nationals made their last real opportunity count by using shortstop Pete Kozma’s fielding error in the eighth as the spark for the winning rally.

The Nationals trailed 2-1 with two outs and runners on second and third in the eighth when Johnson summoned infielder Chad Tracy to pinch hit against reliever Mitchell Boggs. Cardinals manager Mike Matheny responded by yanking Boggs for lefty Marc Rzepczynski. Johnson went back to his bench and used the rookie Moore, who then stroked a two-run single.

“I thought that I had the upper-hand, because I was going to control the matchup,” Johnson said, adding he was surprised Matheny removed Boggs.

Matheny said he would have used closer Jason Motte, but didn’t have a double switch available that would have kept the right-hander in the game for the ninth.

“That left us [Rzepczynski] against one of their young, right-handed hitters and he went up there and put together a good at-bat and that was the game,” Matheny said.

The rally started with Michael Morse’s grounder that rolled off Kozma’s glove for an error. Ian Desmond followed with a single and Danny Espinosa sacrificed Desmond to second. After Kurt Suzuki struck out, Moore got his chance.

“I’m just glad to have the opportunity, because they didn’t want to face Chad Tracy, who is our best pinch-hitter off the bench,” Moore said.

Johnson, a strong candidate for NL Manager of the Year after leading the Nationals to the league’s best record, had last won a postseason game managing the Orioles in 1997. He was the manager when the Mets won their last World Series, in 1986.

With Nationals ace Stephen Strasburg shut down for the season after last month reaching his innings limit, Johnson entrusted the ball to Cy Young award hopeful Gio Gonzalez, who led the NL with 21 victories. But Gonzalez was a mess, walking seven batters over five innings in which he allowed two runs on one hit.

The Cardinals missed a big chance to build a cushion in the seventh, when Yadier Molina hit into an inning-ending double play with the bases loaded. This after reliever Ryan Mattheus had entered and got Allen Craig to hit into a fielder’s choice.

“We did have our opportunities, and certainly with the bases loaded and nobody out they don’t get much better than that,” Matheny said.

Cardinals starter Adam Wainwright lasted 5 2/3 innings and allowed one run on six hits and three walks with 10 strikeouts.

Wainwright, who missed the Cardinals’ magical run to the world championship last season while recovering from Tommy John surgery, became the first Cardinals pitcher since Bob Gibson in Game 4 of the 1968 World Series to reach double digits in strikeouts in a postseason game.

Gonzalez threw 71 pitches through three innings for the Nationals, but somehow managed to last five. His brutal inning was the second, when Gonzalez walked four batters, allowing two runs without a hit. But the Cardinals were done scoring.

“The secret formula this year has been pitching for us,” Desmond said. “Not many people have probably watched too many Nationals games, but we have got a great starting rotation and great bullpen.”